A so-called top-blow type core molding machine in which a blow head is arranged above a core box so as to blow core sand down into the core box from thereabove has conventionally been used (e.g., Patent Literature 1).
In the case of the top-blow type core molding machine, however, the blow head is arranged above the core box, and a sand tank is further arranged above the blow head. This increases the size of the machine in its height direction, which may make the machine bulky. For reducing the size of the machine in its height direction and making it smaller in size, a so-called under-blow type in which a blow head is arranged under a core box so as to blow core sand up into the core box from thereunder may be employed. However, the under-blow type blows the core sand into the core box against gravity and thus may affect the filling property of the core sand for the core box.